Improvements for the Western North Atlantic, Caribbean and Gulf of Mexico ADCIRC Tidal Database (EC2015)

Abstract

This research details the development and validation of an updated constituent tidal database for the Western North Atlantic, Caribbean and Gulf of Mexico (WNAT) region, referred to as the EC2015 database. Regional databases, such as EC2015, provide much higher resolution than global databases allowing users to more accurately define the tidal forcing on smaller sub-region domains. The database last underwent major updates in 2001 and was developed using the two-dimensional, depth-integrated form of the coastal hydrodynamic model, ADvanced CIRCulation (ADCIRC), which solves the shallow-water equations in the generalized wave continuity equation form. Six main areas of improvement are examined: (1) placement of the open ocean boundary; (2) higher coastal resolution using Vertical Datum (VDatum) models; (3) updated bathymetry from global databases; (4) updated boundary forcing compared using two global tidal databases; (5) updated bottom friction formulations; and (6) improved model physics by incorporating the advective terms in ADCIRC. The skill of the improved database is compared to that of its predecessor and is calculated using harmonic data from the National Oceanic and Atmospheric Administration Center for Operational Oceanographic Products and Services (NOAA CO-OPS) stations and historic International Hydrographic Organization (IHO) data. Overall, the EC2015 database significantly reduces errors realized in the EC2001 database and improves the quality of coastal tidal constituents available for smaller sub-regional models in the Western North Atlantic, Caribbean and Gulf of Mexico (WNAT) region.

Improvements for the Eastern North Pacific ADCIRC Tidal Database (ENPAC15)

“…The methodology of this study closely follows that used for the development of the EC2015 tidal database for the eastern coast of the United States [26]; therefore, the entire outline and much of the text provided in Section 2.1, Section 2.2, and Section 2.3 is similar to that of our previous study (in order that this paper is complete enough to stand alone for those readers who are not familiar with that study). While the methodology is similar, it is not the same, due to peculiarities of local regions, so readers are cautioned not to skip these sections entirely.…”

“…Further tests on the ENPAC03 model domain revealed that the presence of the shelf break across the open ocean boundary to the west prevented stable runs when ADCIRC's advective terms were enabled for use (this was confirmed upon examination of the ENPAC03 report as well [27]). Experience gained while updating the Western North Atlantic ADCIRC tidal constituent database revealed that the advective terms played an important role in reducing errors in the shallow near-shore regions [26]. In order to avoid the S2 amphidrome off the Aleutian Islands, an attempt was made to extend the ENPAC03 domain just west of the shelf near longitude −180 • .…”

“…The remainder of the domain was assigned shelf-wide values based on anecdotal evidence since no data was available and a depth-interpolation method similar to that used for the EC2015 database was used [26]. Namely, each larger coastal area was assigned a descriptive designation with an associated range of Manning's n values based upon typical values from literature.…”

“…Therefore, it is necessary to create regional tidal databases with higher resolution that can better represent the near-shore environment. Often, these highresolution products are created for specific marine environments, for example: east Florida [23], Western North Atlantic Ocean [24][25][26], Eastern North Pacific Ocean [27] and Western Europe [28].…”

Steps towards Modeling Community Resilience under Climate Change: Hazard Model Development

“…The Advanced Circulation (ADCIRC [50]) model serves as the hydrodynamic model in the STORM-CoRe coupled model system. ADCIRC, which has been in use for over 35 years, has seen a wide variety of applications, which include flood inundation maps for coastal areas [51,52], modeling baroclinic driven circulation [53], real-time prediction of storm surge to provide guidance [13,21], surge and riverine flooding [14,[54][55][56], modeling tides and wind driven circulation [57,58] and an integrated, scenario-based evacuation and sheltering system [56,59]. The ADCIRC model employs the shallow water equations in their non-linear formulation, subject to hydrostatic and Boussinesq approximations.…”